extends Node
class_name ImpactSpawner

static var bullet_hole_mat: StandardMaterial3D = null
static var crater_mat: StandardMaterial3D = null
static var plasma_mat: StandardMaterial3D = null
static var slash_mat: StandardMaterial3D = null

static func _ensure_mats():
	if bullet_hole_mat != null:
		return
		
	var make_tex = func(colors: Array, offsets: Array, size: int) -> Texture2D:
		var g = Gradient.new()
		# For Godot 4 Gradient, we set offsets and colors directly
		var p_offsets = PackedFloat32Array()
		var p_colors = PackedColorArray()
		for o in offsets: p_offsets.append(o)
		for c in colors: p_colors.append(c)
		g.offsets = p_offsets
		g.colors = p_colors
		# Hard color steps: reads as inked cel splats instead of soft airbrush
		g.interpolation_mode = Gradient.GRADIENT_INTERPOLATE_CONSTANT

		var t = GradientTexture2D.new()
		t.gradient = g
		t.fill = GradientTexture2D.FILL_RADIAL
		t.fill_from = Vector2(0.5, 0.5)
		t.fill_to = Vector2(0.5, 0.0)
		t.width = size
		t.height = size
		return t
		
	var tex_b = make_tex.call(
		[Color(0.01, 0.01, 0.01, 1.0), Color(0.1, 0.1, 0.1, 0.8), Color(0.1, 0.1, 0.1, 0.0)],
		[0.0, 0.3, 1.0], 32)
	bullet_hole_mat = StandardMaterial3D.new()
	bullet_hole_mat.albedo_texture = tex_b
	bullet_hole_mat.transparency = BaseMaterial3D.TRANSPARENCY_ALPHA
	
	var tex_c = make_tex.call(
		[Color(0.05, 0.05, 0.05, 0.9), Color(0.1, 0.1, 0.1, 0.6), Color(0.1, 0.1, 0.1, 0.0)],
		[0.0, 0.5, 1.0], 128)
	crater_mat = StandardMaterial3D.new()
	crater_mat.albedo_texture = tex_c
	crater_mat.transparency = BaseMaterial3D.TRANSPARENCY_ALPHA
	
	var tex_p = make_tex.call(
		[Color(0.8, 0.9, 1.0, 1.0), Color(0.2, 0.6, 1.0, 0.8), Color(0.1, 0.3, 0.8, 0.0)],
		[0.0, 0.2, 1.0], 64)
	plasma_mat = StandardMaterial3D.new()
	plasma_mat.albedo_texture = tex_p
	plasma_mat.transparency = BaseMaterial3D.TRANSPARENCY_ALPHA
	plasma_mat.emission_enabled = true
	plasma_mat.emission_texture = tex_p
	plasma_mat.emission_energy_multiplier = 2.0
	
	var tex_s = make_tex.call(
		[Color(0.9, 0.9, 0.9, 1.0), Color(0.8, 0.8, 0.8, 0.8), Color(0.8, 0.8, 0.8, 0.0)],
		[0.0, 0.5, 1.0], 64)
	slash_mat = StandardMaterial3D.new()
	slash_mat.albedo_texture = tex_s
	slash_mat.transparency = BaseMaterial3D.TRANSPARENCY_ALPHA

static func spawn(scene_tree: SceneTree, type: String, pos: Vector3, normal: Vector3, size: float = 0.2):
	_ensure_mats()

	# Positional impact tick (pooled; safe at fire-rate frequency)
	if type == "bullet":
		var am = scene_tree.root.get_node_or_null("AudioManager")
		if am and am.has_sound("bullet_impact"):
			am.play_3d("bullet_impact", pos, -6.0)
	
	var mi = MeshInstance3D.new()
	var qm = QuadMesh.new()
	
	if type == "slash":
		qm.size = Vector2(size * 4.0, size * 0.4)
	else:
		qm.size = Vector2(size, size)
	
	var mat: StandardMaterial3D
	if type == "bullet":
		mat = bullet_hole_mat.duplicate()
	elif type == "crater":
		mat = crater_mat.duplicate()
	elif type == "plasma":
		mat = plasma_mat.duplicate()
	elif type == "slash":
		mat = slash_mat.duplicate()
		
	qm.material = mat
	mi.mesh = qm
	
	scene_tree.current_scene.add_child(mi)
	
	mi.global_position = pos + normal * 0.01
	
	if abs(normal.dot(Vector3.UP)) < 0.999:
		mi.look_at(mi.global_position - normal, Vector3.UP)
	else:
		mi.look_at(mi.global_position - normal, Vector3.RIGHT)
		
	var duration = 5.0 if type == "crater" else 3.0
	var tween = mi.create_tween()
	tween.tween_interval(duration)
	tween.tween_property(mat, "albedo_color:a", 0.0, 1.0)
	tween.tween_callback(mi.queue_free)